9 - Obstruction Flashcards
What are some non malignant causes of changes to urinary flow?
- BPH
- UTI
- Urinary tract stone disease
- Urological emergencies (urinary retention, acute loin pain, acute renal failure, systemic sepsis, spinal cord compression)
- Urological trauma
What are causes of urinary retention?
Calculi
Pregnancy
BPH
Recent surgery
Drugs
Urethral strictures
Pelviureteric junction obstruction
Pelvic masses
Constipation
Inflammation
Neurogenic disorders

How does acute ureteric obstruction present, what is it usually caused by and how do we diagnose it?
- Renal colic due to calculus
- Acute severe flank pain radiating to groin
- Can be pyonephrosis on top
- Need plain CT or ultrasound
- Emergency as can develop sepsis

How does chronic ureteric obstruction present, what is it usually caused by and how do we diagnose it?
- Painless
- Bi or uni lateral
- Often found incidentally or during renal failure
- Often due to external obstruction

What is the definition of obstructive uropathy?
Renal impairment due to bilateral or uni lateral ureteric obstruction, or high pressure chronic retention
It is a cause of high pressure chronic retention and can get hyperkalaemia as reflux back into kidneys

What is pyonephrosis?
Infection of the kidneys’ collecting system due to obstruction. Pus collects in the renal pelvis and causes distension of the kidney. It can cause kidney failure and sepsis so treat like septic patient

Apart from CT and ultrasound, how can we diagnose that a dilated kidney is due to obstruction?

What is the presentation of ureteric colic?

How can you treat ureteric obstuction?
Decompress if emergency as risk of sepsis and then one of these procedures

What is pelviureteric junction obstruction?
- Often congenital but can present at any stage in life or be asymptomatic and found on imaging by hydronephrosis
- Often loin pain worse after heavy fluid intake or alcohol
- Laproscopic pyeloplasty

What is retroperitoneal fibrosis?
Fibrosis around the aorta that can pull the ureters in and cause an obstruction
Need to decompress, exclude malignancy and give immunosuppression

What is the difference between acute and chronic urinary retention?
Chronic can be painful when acute on chronic and can also be high pressure or low pressure

What is the definition of urinary retention?
- Inability to voluntarily urinate
- Acute urinary retention is the sudden and often painful inability to void despite having a full bladder
- Chronic urinary retention is painless retention associated with an increased volume of residual urine

What are some causes of urinary retention in men and women?

How do we treat acute urinary retention?
- Catheterise and record residual volume first
- History
- Exam e.g abdomen, DRE, genitalia
- Urine Dip
- Treat causes like constipation or alpha blocker for prostate issues

How should you treat someone with acute urinary retention due to issues with their prostate?
- Alpha blocker
- TWOC after 1-2 weeks of blocker
- If fails do TURP

What is the difference between high and low pressure chronic urinary retention?

How should we manage chronic urinary retention?
High pressure: same as acute e.g catheterise etc, but cannot TURP so need constant catheter
Low pressure: TURP works in 50% but usually intermitten self catheterisation or long term catheter
Monitor overnight for post obstructive diuresis

What is post-obstructive diuresis?
Prolonged urine production for at least two consecutive hours immediately following the relief of urinary retention. Can lrad to dehydration and electrolyte imbalance so might need fluids

What are some ways of treating bladder stones?
- Percutaneous suprapubic cystolitholapaxy
- Open cystostomy
- Lithotripsy
What is prostatitis?
Inflammation of the prostate
Can cause obstrutction
What are the main pathogens in Acute Prostatitis?
E. coli
Proteus
Staphylococcus
C. trachomatis
Neisseria gonorrhoeae
Bacteria can be pushed up when inserting a catheter and urine then no longer flushes bacteria back out
What are general and local symptoms of acute prostatitis?
General:
- malaise
- rigors
- fever
Local:
- difficulty passing urine
- dysuria
- perineal tenderness
How does prostatitis present on examination?
Rectal examination reveals a soft, tender and enlarged prostate
How can you get Chronic Prostatitis?
Inadequately treated infection
Some antibodies can’t penetrate the prostate effectively
Recurrent prostatic and urinary tract infections
Occasionally asymptomatic
How can you confirm chronic prostatitis?
Histological examination showing neutrophils, plasma cells and lymphocytes
Positive culture from a sample of prostatic secretion
What is Non-Bacterial Prostatitis?
Most common type of prostatitis
Results in enlargement of the prostate
Difficult to identify bacteria but normally C. trachomatis - normally sexually active men affected
Fibrosis as a result of chronic inflammation
What is Benign Prostatic Hypertrophy (BPH)
Detectable in nearly all men 60+
Non-neoplastic enlargement of the prostate gland
Can lead to bladder outflow obstruction
Can be related to levels of testosterone
Digital rectal exam - firm, smooth and rubbery
What is the pathology with testosterone behind BPH
Testosterone is a androgen
5 alpha reductase converts testosterone → dihydrotestosterone
This can inflame prostate
How does BPH present?
- Difficulty starting to urinate
- A poor stream
- Dribbling postmictruition
- Frequency and nocturia
What can BPH lead to?
- Acute urinary retention
- Desperate urge to pass urine
- Progressive bladder distension → chronic painless retention and overflow incontinence
- CKD
What treats BPH?
- Alpha blockers - relax smooth muscle at bladder neck and within prostate
- Finasteride (5a-reductase inhibitor) presents the formation of di-hydrotetosterone
- Transurethral resection of the prostate (TURP) - widens the urethra